Bad implementation of FlatExponential's getMassDensity

Based on the documentation for FlatExponential it seems that the intended result is to have an exponentially changing density along some specified axis.

However, the getMassDensity member does not respect that axis at all and instead simply calculates the height parameter as Abs[vec{r} - vec{anchor}]. This means that if you define the anchor point as (0,0,0), the result of getMassDensity will be the same at a location of (1,0,0) and (0,1,0) and (0,0,1) and (-1,0,0), regardless of the direction of the axis.

I can't tell if this is just a mistake and should have been (vec{r} - vec{anchor}) dot n_axis, or if this was meant to be used as an exponentially changing spherical volume but with a bad naming scheme as this is not-flat.